The present invention is directed to computer control devices for bicycle devices and, more particularly, to a method and apparatus for selecting a processing mode for a computer controlled bicycle transmission.
Many computer controlled bicycle transmissions have been designed over the years. The goal of such systems usually is to shift the bicycle transmission so that the rider exerts a relatively constant pedaling effort or maintains a substantially constant pedaling rate. Known systems accomplish this in a number of ways. Some systems use the speed of the bicycle to determine when to shift the bicycle transmission. Other systems use the pedaling rate to determine when to shift the bicycle transmission. Yet other systems use a combination of bicycle speed and pedaling rate. Even more sophisticated systems use tension or compression of drive train components, either alone or in combination with bicycle pedaling speed and/or pedaling rate, to determine how much effort is being used to pedal the bicycle and to shift the transmission accordingly. Some systems even use external variables such as the rider""s heart rate to determine when to shift the bicycle transmission. Regardless of the system used, it is sometimes desirable to process the input data (bicycle speed, pedaling rate, tension or compression of drive train components, heart rate, etc.) differently under different circumstances. For example, it may be desirable to process the input data one way when riding on a level road and in a different way when riding in mountainous terrain.
One way to switch algorithms used to process the input data is to provide one or more switches on a handlebar mounted shift control device to select the desired algorithm. However, such switches ordinarily must be pressed alone or in combination in a particular sequence that often is not intuitive at all. Also, such switches add to the cost and complexity of the shift control device, are subject to contamination and malfunctioning, and must be constantly powered, thus reducing battery life.
The present invention is directed to a method and apparatus for selecting a processing mode for a bicycle computer which does not require separate switches on the shift control device or complicated procedures to select the desired processing mode. In one embodiment of the present invention, a mechanism for selecting a processing mode for a bicycle computer includes a mounting member adapted to be mounted on a first bicycle component; a first signal sensor retained to the mounting member; a second signal sensor retained to the mounting member; and a first signal provider for providing a first signal and arranged to be disposed in a predetermined plurality of positions relative to the first signal sensor and the second signal sensor. The algorithm used to control the desired component may be selected based on whether the first signal is sensed by the first signal sensor and/or the second signal sensor.
More specifically, a processor may be operatively coupled to the first signal sensor and to the second signal sensor for performing a first sequence of calculations when the first signal sensor senses the first signal and for performing a second sequence of calculations different from the first sequence of calculations when the second signal sensor senses the first signal. In a more specific embodiment, the processor performs a third sequence of calculations when both the first signal sensor and the second signal sensor sense the first signal, wherein the third sequence of calculations may be different from the first sequence of calculations and the second sequence of calculations.
Typically, the signal provider may be temporarily or permanently placed in close proximity to the first signal sensor so that the processor performs the first sequence of calculations, and then the signal provider may be temporarily or permanently placed in close proximity to the second signal sensor so that the processor performs the second sequence of calculations. If the first signal sensor and the second signal sensor are placed close to each other, then the first signal provider may be somewhat centered over the first signal sensor and the second signal sensor so that both the first and second signal sensors are activated and thereby cause the processor to perform the third sequence of calculations. If desired, the first signal provider may be large enough to provide a signal to both the first signal sensor and the second signal sensor. In this case a signal filter may be provided for selectively communicating the first signal to the first signal sensor and/or the second signal sensor.
As applied to a bicycle, a mechanism for selecting a processing mode for a bicycle computer includes a first bicycle component and a second bicycle component, wherein at least one of the first bicycle component and the second bicycle component moves relative to the other one of the first bicycle component and the second bicycle component. A signal provider is retained to the first bicycle component, wherein the signal provider provides a first signal. A first signal sensor is retained to the second bicycle component, and a second signal sensor is retained to the second bicycle component. A processor is operatively coupled to the first signal sensor and to the second signal sensor for performing a first sequence of calculations when the first signal sensor senses the first signal and for performing a second sequence of calculations different from the first sequence of calculations when the second signal sensor senses the first signal. In a more specific embodiment, the at least one of the first bicycle component and the second bicycle component rotates relative to the other one of the first bicycle component and the second bicycle component around a rotational axis. If desired, the first bicycle component may be one of a bicycle frame member and a bicycle wheel, and the second bicycle component may be the other one of the bicycle frame member and the bicycle wheel. Alternatively, the first bicycle component may be one of a bicycle frame member and a pedal crank, and the second bicycle component may be the other one of the bicycle frame member and the pedal crank.